Oscillating mobile device position determination

Abstract

A method in a mobile device includes: receiving location signals at the mobile device; measuring sensor data at the mobile device; determining an oscillation rate of the mobile device from the sensor data; in response to the oscillation rate of the mobile device being undesirable, at least one of: (1) determining a desired sampling rate based on the oscillation rate, the desired sampling rate being different from the oscillation rate; and sampling the location signals at the mobile device at the desired sampling rate; (2) sampling the location signals at the mobile device at a randomized sampling rate; (3) disabling a power improvement technique; (4) increasing filtering of determined course information; (5) reducing a nominal filter bandwidth; or (6) increasing a present sampling rate of the location signals to satisfy Nyquist criteria for the oscillation rate; and determining the position associated with the mobile device using the location signals.

What is claimed is: 
     
         1 . A method in a mobile device for determining a position associated with the mobile device, the method comprising:
 receiving location signals at the mobile device;   measuring sensor data at the mobile device;   determining an oscillation rate of the mobile device from the sensor data;   in response to the oscillation rate of the mobile device being undesirable, at least one of:
 (1) determining a desired sampling rate based on the oscillation rate, the desired sampling rate being different from the oscillation rate; and 
 sampling the location signals at the mobile device at the desired sampling rate; 
 (2) sampling the location signals at the mobile device at a randomized sampling rate; 
 (3) disabling a power improvement technique; 
 (4) increasing filtering of determined course information; 
 (5) reducing a nominal filter bandwidth; or 
 (6) increasing a present sampling rate of the location signals to satisfy Nyquist criteria for the oscillation rate; and 
   determining the position associated with the mobile device using the location signals.   
     
     
         2 . The method of  claim 1  wherein the oscillation rate is undesirable if the oscillation rate is associated with aliasing, and wherein the desired sampling rate is faster than the oscillation rate of the mobile device. 
     
     
         3 . The method of  claim 1  wherein measuring sensor data comprises measuring sensor data from at least one of an accelerometer, a magnetometer, a pedometer, a barometric pressure sensor, or a gyroscope. 
     
     
         4 . The method of  claim 1  wherein the oscillation rate is undesirable if the oscillation rate is indicative of pedestrian motion and is similar to the present sampling rate of the location signals. 
     
     
         5 . The method of  claim 1  wherein the oscillation rate is undesirable if the oscillation rate is indicative of substantially uniform pedestrian motion for longer than a threshold length of time and is similar to the present sampling rate of the location signals. 
     
     
         6 . The method of  claim 1  further comprising determining an oscillation magnitude of the mobile device and wherein at least one of operations (1)-(6) are performed in response to the oscillation rate of the mobile device and the oscillation magnitude of the mobile device both being indicative of substantially uniform pedestrian motion for longer than a threshold length of time. 
     
     
         7 . The method of  claim 1  wherein the oscillation rate is undesirable if the oscillation rate is sufficiently similar to the present sampling rate to induce an oscillation error greater than a threshold error. 
     
     
         8 . A mobile device comprising:
 a receiver configured to receive location signals;   a sensor configured to measure sensor data;   rate determining means, communicatively coupled to the sensor, for determining an oscillation rate of the mobile device from the sensor data;   desirability means for determining whether the oscillation rate is undesirable;   at least one of:
 (1) sampling rate means, communicatively coupled to the rate determining means, for determining a desired sampling rate based on the oscillation rate; and 
 first sampling means, communicatively coupled to the sampling rate means, the desirability means, and the receiver, for sampling the location signals at the desired sampling rate in response to the desirability means determining that the oscillation rate is undesirable; 
 (2) second sampling means, communicatively coupled to the desirability means, for sampling the location signals at a randomized sampling rate in response to the desirability means determining that the oscillation rate is undesirable; 
 (3) disabling means, communicatively coupled to the desirability means, for disabling a power improvement technique in response to the desirability means determining that the oscillation rate is undesirable; 
 (4) first filtering means, communicatively coupled to the desirability means, for increasing filtering of course information determined from the location signals in response to the desirability means determining that the oscillation rate is undesirable; 
 (5) second filtering means, communicatively coupled to the desirability means, for reducing a nominal filter bandwidth in response to the desirability means determining that the oscillation rate is undesirable; 
 (6) third sampling means, communicatively coupled to the desirability means, for increasing a present sampling rate of the location signals to satisfy Nyquist criteria for the oscillation rate in response to the desirability means determining that the oscillation rate is undesirable; and 
   a position module configured to determine a position of the mobile device using the location signals.   
     
     
         9 . The mobile device of  claim 8  wherein the oscillation rate is undesirable if the oscillation rate is associated with aliasing, and wherein the desired sampling rate is faster than the oscillation rate. 
     
     
         10 . The mobile device of  claim 8  wherein the sensor comprises at least one of an accelerometer, a magnetometer, a pedometer, a barometric pressure sensor, or a gyroscope. 
     
     
         11 . The mobile device of  claim 8  wherein the oscillation rate is undesirable if the oscillation rate is indicative of pedestrian motion and is similar to the present sampling rate of the location signals. 
     
     
         12 . The mobile device of  claim 8  wherein the oscillation rate is undesirable if the oscillation rate is indicative of substantially uniform pedestrian motion for longer than a threshold length of time and is similar to the present sampling rate of the location signals. 
     
     
         13 . The mobile device of  claim 8  further comprising magnitude means for determining a magnitude of oscillation of the mobile device, wherein at least one of the sampling rate means, first sampling means, second sampling means, third sampling means, disabling means, first filtering means, or second filtering means, are responsive to the oscillation rate and the magnitude of oscillation of the mobile device being indicative of substantially uniform pedestrian motion for longer than a threshold length of time. 
     
     
         14 . The mobile device of  claim 8  wherein the oscillation rate is undesirable if the oscillation rate is sufficiently similar to the present sampling rate to induce an oscillation error greater than a threshold error. 
     
     
         15 . A mobile device comprising:
 a receiver configured to receive location signals;   a sensor configured to measure sensor data;   a processor, communicatively coupled to the sensor and the receiver, configured to:
 determine an oscillation rate of the mobile device from the sensor data; and 
 respond to the oscillation rate being undesirable to at least one:
 (1) determine a desired sampling rate based on the oscillation rate; and
 cause the location signals to be sampled at the desired sampling rate; 
 
 (2) cause the location signals to be sampled at a randomized sampling rate; 
 (3) disable a power improvement technique; 
 (4) increase filtering of course information determined from the location signals; 
 (5) reduce a nominal filter bandwidth; 
 (6) increase a present sampling rate of the location signals to satisfy Nyquist criteria for the oscillation rate; and 
 
 determine a position of the mobile device using the location signals. 
   
     
     
         16 . The mobile device of  claim 15  wherein the oscillation rate is undesirable if the oscillation rate is associated with aliasing, and wherein the desired sampling rate is faster than the oscillation rate. 
     
     
         17 . The mobile device of  claim 15  wherein the sensor comprises at least one of an accelerometer, a magnetometer, a pedometer, a barometric pressure sensor, or a gyroscope. 
     
     
         18 . The mobile device of  claim 15  wherein the oscillation rate is undesirable if the oscillation rate is indicative of pedestrian motion and is similar to the present sampling rate of the location signals. 
     
     
         19 . The mobile device of  claim 15  wherein the oscillation rate is undesirable if the oscillation rate is indicative of substantially uniform pedestrian motion for longer than a threshold length of time and is similar to the present sampling rate of the location signals. 
     
     
         20 . The mobile device of  claim 15  wherein the processor is further configured to:
 determine a magnitude of oscillation of the mobile device; and 
 respond to the oscillation rate and the magnitude of oscillation of the mobile device being indicative of substantially uniform pedestrian motion for longer than a threshold length of time to perform at least one of operations (1)-(6). 
 
     
     
         21 . The mobile device of  claim 15  wherein the oscillation rate is undesirable if the oscillation rate is sufficiently similar to the present sampling rate to induce an oscillation error greater than a threshold error. 
     
     
         22 . A processor-readable storage medium comprising processor-readable instructions configured to cause a processor to:
 determine an oscillation rate of a mobile device from mobile device sensor data; and   respond to the oscillation rate being undesirable to at least one:
 (1) determine a desired sampling rate based on the oscillation rate; and
 cause received location signals to be sampled at the desired sampling rate; 
 
 (2) cause the location signals to be sampled at a randomized sampling rate; 
 (3) disable a power improvement technique; 
 (4) increase filtering of course information determined from the location signals; 
 (5) reduce a nominal filter bandwidth; 
 (6) increase a present sampling rate of the location signals to satisfy Nyquist criteria for the oscillation rate; and 
   determine a position of the mobile device using the location signals.   
     
     
         23 . The processor-readable storage medium of  claim 22  wherein the oscillation rate is undesirable if the oscillation rate is associated with aliasing, and wherein the desired sampling rate is faster than the oscillation rate. 
     
     
         24 . The processor-readable storage medium of  claim 22  wherein the oscillation rate is undesirable if the oscillation rate is indicative of pedestrian motion and is similar to the present sampling rate of the location signals. 
     
     
         25 . The processor-readable storage medium of  claim 22  wherein the oscillation rate is undesirable if the oscillation rate is indicative of substantially uniform pedestrian motion for longer than a threshold length of time and is similar to the present sampling rate of the location signals. 
     
     
         26 . The processor-readable storage medium of  claim 22  further comprising instructions configured to cause the processor to:
 determine a magnitude of oscillation of the mobile device; and 
 respond to the oscillation rate and the magnitude of oscillation of the mobile device being indicative of substantially uniform pedestrian motion for longer than a threshold length of time to perform at least one of operations (1)-(6). 
 
     
     
         27 . The processor-readable storage medium of  claim 22  wherein the oscillation rate is undesirable if the oscillation rate is sufficiently similar to the present sampling rate to induce an oscillation error greater than a threshold error.